I really don't get the seeming dismissal of masks as a tool to contain spread. I understand that there's a shortage and healthcare workers are the priority (as they should be), but it seems to me that in theory the absolute fastest way to contain this would be to get everyone on the planet wearing masks for a month or two.
I keep seeing statements to the effect of "a mask only helps if you're already sick", but we don't know who's sick and who isn't! The only way to ensure all the sick people are wearing masks is to get everyone wearing masks. But perhaps it isn't possible to ramp up production fast enough to make this realistic?
You can't ramp production that fast, especially since so many factories moved to China. So given a limited resource, you have to discourage people from buying out all the supply so you can preserve your healthcare capability of the medical staff. I would guess it's a judgement call that ensuring medical personnel have masks is a greater epidemic fighting effect relative to the epidemic reduction in casual people wearing masks.
You can always publicise an alternate policy when the mask supply does increase later..
Masks are dangerous if worn improperly. They can create a warm moist environment on your face that promotes microbial growth. Also, the mask itself can get infected. Disposable masks aren't built to he reused and cleaned, so you can end up transferring the infection around on your mask if you reuse a disposable. Finally, the idea that masks reduce touching your face might be false, it's possible something itchy and irritating like a mask caused people to touch their faces more.
Afaik the primary method of transmission is believed to be saliva droplets in the air, expelled via talking, sneezing, or coughing. I think even a badly fitting mask would cut this drastically?
Washing hands, avoiding touching your face, and other measures like these mainly help with what seems to be a far less common vector of transmission via surfaces and physical contact, where the virus only remains active for a very short time.
You have it backwards. Droplets on surfaces are the primary transmission mechanism. The virus can survive on surfaces for hours. People then touch surfaces with their hands then touch their faces.
Droplets in the air are a transmission mechanism but only for short range (3-6 feet) and only a danger from people who cough or sneeze on you. Respirators are effective at stopping that transmission but they are most useful for people treating the sick. But they aren't effective if worn improperly. For most people, avoiding the sick is enough.
Surgical masks are useful for the sick to keep cough and sneeze droplets from spreading. They are also useful to keep people from touching their face.
The last one - Aerosol transmission - really adds to why this virus is so infectious.
Unlike balistic droplets, an aerosol plume can stay in a room for a very long time after someone coughs or sneezes. An aerosol plume can stay in the air long after someone flushes fecal matter down a toilet.
As a comparison aerosol transmission is what makes tuberculosis and measle so challenging in terms of containment and infection rate.
Thanks for this perspective, but this conflicts with other info I'm seeing. It's hard to know what to believe--do you have any good sources supporting this?
"The new coronavirus spreads mostly through person-to-person contact within about a 6-foot (1.8 meters) radius, according to the Centers for Disease Control and Prevention (CDC). People with COVID-19, which is the disease caused by the coronavirus, spread viral particles through coughing and sneezing. The particles can land in the mouths or noses of those nearby.
It might also be possible to catch SARS-CoV-2 by touching a surface where the virus has recently landed and then touching one's mouth, nose or eyes, but CDC officials believe this method of transmission is less common."
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I really don't get the seeming dismissal of masks as a tool to contain spread. I understand that there's a shortage and healthcare workers are the priority (as they should be), but it seems to me that in theory the absolute fastest way to contain this would be to get everyone on the planet wearing masks for a month or two.
I keep seeing statements to the effect of "a mask only helps if you're already sick", but we don't know who's sick and who isn't! The only way to ensure all the sick people are wearing masks is to get everyone wearing masks. But perhaps it isn't possible to ramp up production fast enough to make this realistic?
You can't ramp production that fast, especially since so many factories moved to China. So given a limited resource, you have to discourage people from buying out all the supply so you can preserve your healthcare capability of the medical staff. I would guess it's a judgement call that ensuring medical personnel have masks is a greater epidemic fighting effect relative to the epidemic reduction in casual people wearing masks.
You can always publicise an alternate policy when the mask supply does increase later..
There aren't enough to go around, and they need to be changed after something like 2 hours - or is it 4?
It's easier to just keep people isolated, I guess.
Masks are dangerous if worn improperly. They can create a warm moist environment on your face that promotes microbial growth. Also, the mask itself can get infected. Disposable masks aren't built to he reused and cleaned, so you can end up transferring the infection around on your mask if you reuse a disposable. Finally, the idea that masks reduce touching your face might be false, it's possible something itchy and irritating like a mask caused people to touch their faces more.
The great thing about badly fitting masks is people wearing them tend to touch their face a lot more.
Afaik the primary method of transmission is believed to be saliva droplets in the air, expelled via talking, sneezing, or coughing. I think even a badly fitting mask would cut this drastically?
Washing hands, avoiding touching your face, and other measures like these mainly help with what seems to be a far less common vector of transmission via surfaces and physical contact, where the virus only remains active for a very short time.
You have it backwards. Droplets on surfaces are the primary transmission mechanism. The virus can survive on surfaces for hours. People then touch surfaces with their hands then touch their faces.
Droplets in the air are a transmission mechanism but only for short range (3-6 feet) and only a danger from people who cough or sneeze on you. Respirators are effective at stopping that transmission but they are most useful for people treating the sick. But they aren't effective if worn improperly. For most people, avoiding the sick is enough.
Surgical masks are useful for the sick to keep cough and sneeze droplets from spreading. They are also useful to keep people from touching their face.
Just for completion.
The current understanding is that the transmission mechanisms for Covid-19 are:
1. Contact 2. Droplets (particles > 20 microns), AND 3. Aerosol (particles < 5/10 microns)
The last one - Aerosol transmission - really adds to why this virus is so infectious.
Unlike balistic droplets, an aerosol plume can stay in a room for a very long time after someone coughs or sneezes. An aerosol plume can stay in the air long after someone flushes fecal matter down a toilet.
As a comparison aerosol transmission is what makes tuberculosis and measle so challenging in terms of containment and infection rate.
Thanks for this perspective, but this conflicts with other info I'm seeing. It's hard to know what to believe--do you have any good sources supporting this?
For example, a quick google of "how does coronavirus spread" brings up this article as the top result: https://www.livescience.com/how-coronavirus-spreads.html
It says:
"The new coronavirus spreads mostly through person-to-person contact within about a 6-foot (1.8 meters) radius, according to the Centers for Disease Control and Prevention (CDC). People with COVID-19, which is the disease caused by the coronavirus, spread viral particles through coughing and sneezing. The particles can land in the mouths or noses of those nearby.
It might also be possible to catch SARS-CoV-2 by touching a surface where the virus has recently landed and then touching one's mouth, nose or eyes, but CDC officials believe this method of transmission is less common."
Even a non-surgical or home-made mask is better than no mask at all.